Metallurgical engineers develop ways of processing metals and converting them into useful products. Metallurgy, the science of metals, is one of the materials sciences. Other materials sciences include physical metallurgy, ceramics, and polymer chemistry, or plastics. Metallurgical engineers, a subspecialty of materials engineers, work primarily in industrial areas, particularly in the iron and steel industries. Some work with other metals such as aluminum or copper. Metallurgical engineers are also employed in industries that make machinery and other products using metal, such as automobiles and electrical equipment. Some work for government agencies or colleges and universities.

The work of metallurgical engineers is similar to the work of metallurgical scientists, or metallurgists. Metallurgical engineers use complex equipment, including electron microscopes, X-ray machines, and spectrographs. They use the latest scientific and technological findings in their work. Metallurgical engineers are often assisted by metallurgical technicians.

There are two main branches of metallurgy—extractive metallurgy and physical metallurgy. Extractive metallurgy involves the separation, or extraction, of metals from ores. Ores are mixtures of metals and other substances. Once the ore has been mined, many steps are needed to extract the metal and refine it to a relatively pure form. Metallurgical engineers design and supervise the processes that separate the metals from their ores. They often cooperate with mining engineers in the early steps of the extraction process. After metallic compounds have been separated from the rock and other waste materials, metallurgical engineers can use a number of different processes to refine the metals. These processes might involve the use of heat, electric current, or chemicals dissolved in water to produce a pure and usable metal.

Metallurgical engineers involved in extractive metallurgy work in laboratories, ore treatment plants, refineries, and steel mills. They are concerned with finding new and better ways of separating relatively small amounts of metal from huge quantities of waste rock. They must consider the effects that the process has on the environment, the conservation of energy, and the proper disposal of the waste rock.

Physical metallurgy is the study of the structure and physical properties of metals and alloys. It also involves the many processes used to convert a refined metal into a finished product. Most metals are not useful in their pure form. They must be made into alloys, or mixtures of a metal and one or more other elements. Steel is an example of an alloy. It is made from iron and small amounts of carbon and other elements. Copper and zinc are combined to form another alloy, brass. Scientists and metallurgical engineers work in physical metallurgy to develop new alloys to meet many needs. These alloys include radiation shielding for nuclear reactors, lightweight but high-strength steel for automobile bodies, and special metals used in electronic equipment. Physical metallurgical engineers also develop production processes that include melting, casting, alloying, rolling, and welding. They design and supervise the processes that produce such goods as structural steel, wire, or sheets of aluminum. Sometimes they are involved in processes that use these metal goods in the manufacture of other finished products. Physical metallurgists often work in laboratories or in manufacturing plants.